NATIVE GRASSES AND PUCCINIA GRAMINIS 177 



counties. It is also extremely common in the counties immediately 

 north of these in Minnesota, extending east to Mississippi river. 

 Locally the grass is well etablished in Dubuque county, Iowa, and in 

 the vicinity of Galena, Illinois. It occurs in northern Missouri and 

 southern Iowa, but only in isolated areas. Puccinia graminis was 

 common everywhere in the region. Mention may be made of the 

 following localities where I noted its occurrence : Garner, Britt, 

 Corwith, Forest City, Thompson, Lake Mills, Humboldt, Northwood, 

 Clinton, Dubuque, Keokuk, Burlington, Ottumwa, Des Moines, 

 Ames, Sibley, Spirit Lake, Sioux City, Hamburg, Council Bluffs, 

 Rock Rapids, Little Rock, McGregor, Postville, Clermont and 

 Farley in Iowa ; Hamilton, Zearing, Walnut, LaSalle, East 

 Dubuque, Galena, and Scales Mound in Illinois ; La Crosse, Prairie 

 du Chien, Onalaska, Wisconsin ; Albert Lea, Marshall, Luverne, 

 Granite Falls, Sanborn, Graceville, Ortonville, Minnesota ; La Bolt, 

 Watertown, Humboldt, Mitchell, Brookings, Sioux Falls, South 

 Dakota. 



Hordeum jiibatum L. Squirrel tail grass is widely distributed 

 throughout northern Illinois, Iowa to northern Minnesota, Nebraska 

 and South Dakota, less commonly in southern Iowa and northern 

 Missouri. It is found throughout the region of Iowa and except 

 southward it is one of the most common of our weeds and weedy 

 grasses. Pastures everywhere in June are purple with the bristly 

 tops of this grass and everywhere from July to frost one may find 

 the P. graminis on it. Puccinia graminis was abundant at Forest 

 City, Garner, Corwith, Algona, Rock Rapids, Humboldt and Little 

 Rock in Iowa and at Graceville, Marshall, Ortonville, Luverne, 

 Minnesota ; Watertown, Mitchell, Brookings, Humboldt and Sioux 

 Falls, South Dakota. It was also abundant at La Crosse, Wisconsin. 

 Its course of development and spread during the early autmun 

 months and late summer is rapid. It is of interest to add that all 

 uredo spore development practically ceases with the hard killing 

 frost, which in 1918 was the latter part of November. I may also 

 add that P. graminis did not spread much after the early frosts of 

 October. I watched the grass during much of the winter, which 

 was a mild one. I made observations on squirrel tail grass from 

 November 18, 1918, to April 20, 1919. The severe frosts late in No- 

 vember prevented any further growth of squirrel tail grass. The 

 older stems were covered with the teleutopustules and occasionally 

 some uredo pustules disappeared after the first of December. Even 

 such plants removed to the greenhouse, for another purpose, when 

 they were cut close to the surface of the ground, did not show any 



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